Join Early Retirement Today
Thread Tools Search this Thread Display Modes
Old 06-04-2013, 11:32 AM   #21
Thinks s/he gets paid by the post
John Galt III's Avatar
Join Date: Oct 2008
Posts: 1,033
Originally Posted by travelover View Post
Neither of these provide ventilation for the attic space. If you get a ridge vent, make sure they also install soffit vents for incoming air.
Correction! I was wrong about the vents. I have 2 silver "cake box" vents, one on each slope, that just open into the attic with no hoses attached, and one tube type vent on the front slope (sewer vent?). Also, a gable vent in top of the gable. Looks like all are passive. Never hear a fan running. Also, I have lots of soffet vents in the eaves. I was up in the attic 20 years ago, and saw them. Today I rigged up a mirror on a stick and looked around. It looks like my bathroom fan just vents into the attic through a tube that sticks up about 5 feet above the insulation. Using my mirror on the stick I could not find the "sewer vent" or "vent pipe". Will have to get into the attic again somehow, through that small square access hatch ...... ugh...

John Galt III is offline   Reply With Quote
Join the #1 Early Retirement and Financial Independence Forum Today - It's Totally Free!

Are you planning to be financially independent as early as possible so you can live life on your own terms? Discuss successful investing strategies, asset allocation models, tax strategies and other related topics in our online forum community. Our members range from young folks just starting their journey to financial independence, military retirees and even multimillionaires. No matter where you fit in you'll find that is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with our members, see fewer ads, upload photographs, create a retirement blog, send private messages and so much, much more!

Old 06-04-2013, 11:57 AM   #22
Thinks s/he gets paid by the post
Join Date: Jul 2010
Location: Chicago
Posts: 1,001
You need to make sure your bath vent doesn't just exhaust directly into the attic, if so you need to finish it through the roof or the soffit. You're adding moisture in the attic whenever you run the bath fan which promotes mold growth. You should check all your soffit vents to make sure they're not clogged with dust, debris and loose insulation. If you decide to do ridge venting, you will need to cover up the gable vent to help promote proper airflow from the soffit to ridge vents. Otherwise, you'll just be pulling air from the gable to the ridge when isn't what you really want to do

Dimsumkid is offline   Reply With Quote
Old 06-04-2013, 12:03 PM   #23
Give me a museum and I'll fill it. (Picasso)
Give me a forum ...
Join Date: May 2004
Posts: 10,895
Ridge vents are fine. They are not functionally any better or worse than standard roof vents placed near the ridge, but some people like the look a bit more.

If a home has standard roof construction (an insulated ceiling over the top inhabited floor with a roof over that), then the attic space definitely needs to be ventilated effectively. That means soffit vents (so air can get in) and vents up high (ridge, gable, "box" etc) so the hot air can get out. This is important in hot climates but also very important in cold climates, else the moisture in the warm air from the home will condense on the cold roof/framing and mold/rot will result. Gable vents can be "okay" for the upper vents, but they often need to be very big in order to get the job done (see math below).

How much ventilation is enough? One rule of thumb is that the Net Free Area (NFA) of the top and soffit vents combined should equal 1:150th of the attic size. The NFA is shown on vents of all kinds and accounts for the obstructive effects of screening, bracing, etc: The NFA can typically be about 1/2 of the actual area of the hole for the vent. So, a 2000 sq foot house would need 2000/150=13.33 sq feet total NFA of soffit and top vents. That's about 6.75 sq feet NFA for top vents and 6.75 sq feet NFA of soffit vents.

Soffit vents: Having vents in the soffits does little/no good if the path of the air is blocked by attic insulation. It is important to have trays installed or take other steps to assure the air can get up into the attic.

Originally Posted by John Galt III View Post
Today I rigged up a mirror on a stick and looked around. It looks like my bathroom fan just vents into the attic through a tube that sticks up about 5 feet above the insulation.
That's a bad setup. Even worse: I've seen clothes dryers vented that way, rather than going outside. Every load of laundry= a gallon or two of water piped up there to the attic to cause mayhem (condense on the roof/truusses in the winter, condense on the ceiling and add to the heating load in the summer). Bathrooms, clothes dryers, stove hoods should all be vented to the outside through a vent in the roof, wall, or (less good but far better than the attic) through a dedicated vent out through the soffit.

For what it's worth.

"Freedom begins when you tell Mrs. Grundy to go fly a kite." - R. Heinlein
samclem is online now   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


All times are GMT -6. The time now is 03:58 PM.
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.